Audio systems are used in a variety of applications. These applications include consumer and professional applications. Professional applications include entertainment venues such as theaters. For many audio system applications, centrally generated audio is sent to one or more audio zones. For centrally generated audio the input sources are located together at a location that is denoted the central location. This central location can be anywhere in the facility. The centrally generated audio is derived from input sources such as tuners, tape decks, CD players, DVD players, or DSS receivers. A listener located in an audio zone, located remotely from the central location, may use the audio system to listen to audio derived from an input source. Each audio zone can receive audio from the same input source or from distinct input sources depending on the needs of the application and the capabilities of the audio system.
The benefits of an audio system that distributes audio to more than one audio zone include convenient access to audio music in every audio zone within an application (e.g., rooms within a residence), savings in the form of fewer system components, and the ability to provide customized control over the audio as it is distributed to the audio zones. With an audio system that distributes audio the various source components do need to be replicated in each of the various audio zones within a facility.
For some audio systems, a user can not control the audio system from a remote zone. The user must inconveniently go to the central location of the audio system to control the audio music for the remote zone where the user is located. In other audio systems, the system is configured using a relatively elaborate wiring distribution to connect the system's microphones, speakers, and control panels in the various audio zones to a central control circuit which distributes the audio to the zones. In such systems, the user convenience and control over the audio in the zones can be facilitated by providing a control capability located within each remote audio zone. For example, a user can turn down the volume in a particular zone using a manual volume setting control so that the user is not disturbed by continuously playing audio. The user would find it helpful, however, if the volume was returned to its normal listening level in the event that the music is interrupted by a doorbell, a page, or some other special musical or tonal audio signal. Moreover, such an automatic override interruption should be implemented such that no annoying pops are heard at the speaker when an interrupting signal is suddenly presented to the speaker. An ideal audio system provides user control from a remote zone without requiring costly re-routing of control and signal wires in existing systems.
Previous approaches have attempted to improve on some of the above audio-distribution aspects over other features relating to convenience, cost, and/or quality. One approach for remote zone user control implements devices with switches and relays that do not contain any control logic within the device itself. The device may need to be manually reset and may not indicate the on/off status of the audio system. Additionally, if a remote zone volume control is provided, then the volume must be adjusted manually with a rotary or other type switch on the device.
A second approach for remote zone user control uses digital control circuits having up/down volume control. The up/down control is typically implemented with counter logic or a potentiometer. The digital control circuits do not include advanced software control functions and are limited to an incremental up/down control.
A third approach for remote zone user control uses a two piece design that can provide up/down volume control, visual indication of the volume level, and automatic volume resetting after a system shut down. However, the two piece design includes a microprocessor control unit for the remote zone and an additional control unit leading to more difficult installation, particularly for retrofit applications.
Designs of these approaches can benefit from an easier and less time consuming installation and convenient user control from a remote zone. Consequently, realizing an ideal audio system, one that delivers clear audio in a convenient to use manner, minimizes installation time and is adaptable to a various needs associated with audio applications has been challenging.